JavaFX Circle draw random circles with connecting lines

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.layout.Pane;
import javafx.scene.shape.Circle;
import javafx.scene.shape.Line;
import javafx.scene.text.Text;
import javafx.stage.Stage;

public class Main extends Application {
   @Override//from  w  w w . j a v a2  s  .  c o  m
   public void start(Stage primaryStage) {
      final double WIDTH = 500.0;
      final double HEIGHT = 500.0;

      // Create two circles
      Circle c1 = new Circle(getRandom(WIDTH), getRandom(HEIGHT), 15);
      Circle c2 = new Circle(getRandom(WIDTH), getRandom(HEIGHT), 15);

      // Create a line between the centers of the two circles
      Line line = new Line(c1.getCenterX(), c1.getCenterY(), c2.getCenterX(), c2.getCenterY());

      // Get the length of the line
      double distance = distance(c1.getCenterX(), c1.getCenterY(), c2.getCenterX(), c2.getCenterY());

      // Create a text object to display the length
      double maxX = Math.max(c1.getCenterX(), c2.getCenterX());
      double minX = Math.min(c1.getCenterX(), c2.getCenterX());
      double maxY = Math.max(c1.getCenterY(), c2.getCenterY());
      double minY = Math.min(c1.getCenterY(), c2.getCenterY());
      double x = ((maxX - minX) / 2) + minX;
      double y = ((maxY - minY) / 2) + minY;
      Text tDistance = new Text(x, y, distance + "");

      Pane pane = new Pane();
      pane.getChildren().addAll(c1, c2, line, tDistance);

      Scene scene = new Scene(pane, WIDTH, HEIGHT);
      primaryStage.setTitle("java2s.com");
      primaryStage.setScene(scene);
      primaryStage.setResizable(false);
      primaryStage.show();
   }

   public static double getRandom(double n) {
      return Math.random() * n;
   }

   public static double distance(double x1, double y1, double x2, double y2) {
      return Math.sqrt(Math.pow(x1 - x2, 2) + Math.pow(x2 - y2, 2));
   }

   public static void main(String[] args) {
      Application.launch(args);
   }
}